Method and device for solving direction perception obstacle caused by rotating mirror

Abstract

The invention discloses a method and a device for solving direction perception disorder caused by a rotating mirror, and solves the problem that an adjacent tissue structure outside a part is difficult to determine after endoscopic examination rotation in a similar upper digestive tract wall internal lesion. The method comprises the following steps: acquiring pose information of an endoscope in an electromagnetic navigation system of a lumen target position and a corresponding image in the lumen as a reference pose; obtaining a track pose of the endoscope after the view field is adjusted in the electromagnetic navigation system and a corresponding intraluminal image, and determining an Euler angle of each track point according to the track pose; obtaining a track pose of the endoscope after the view field is adjusted in the electromagnetic navigation system and a corresponding intraluminal image, and determining an Euler angle of each track point according to the track pose; performing three-dimensional reconstruction on the lumen and the adjacent tissue thereof according to the lumen image map, and performing corresponding rotation according to the rotating mirror angle and the corresponding image in the lumen to obtain the rotated lumen and the adjacent tissue thereof; according to the invention, after the endoscope rotates to the optimal visual field, the adjacent tissues outside the endoscope can be clearly known.

Description

Technical Field

[0001] The present invention relates to the technical field of surgical navigation, and in particular to a solution and device for solving direction perception obstacles caused by a rotating mirror. Background Art

[0002] The indications for endoscopic examination of upper gastrointestinal tract wall lesions are very broad, covering almost all benign, pre-malignant and malignant diseases. As the first-line diagnosis and treatment method for digestive system diseases, it has not been replaced so far.

[0003] There are several problems with related technologies for diagnosing intramural lesions, such as upper gastrointestinal endoscopy: ① The endoscopist needs to repeatedly rotate the endoscope to obtain the best observation field of view, and can only observe the situation inside the lumen. ② As the endoscope rotates left and right, the observed intraluminal field of view will also change. Since the lumen of the upper gastrointestinal tract, such as the esophagus, is a tubular structure, the rotational change of the endoscopic field of view will cause the corresponding adjacent structures outside the lumen to visually deviate from the standard anatomical position. ③ Endoscopists need to have solid anatomical knowledge and an absolute sense of direction for rotating the endoscope in order to independently construct the corresponding tissue structure outside the lumen. ④ Regardless of the patient's body shape or different diseases, the anatomical structure outside the lumen is different, and for example, there are no identifiable feature points inside the esophageal lumen. ⑤ This makes it impossible for doctors to accurately identify the four walls of the lumen after rotating the field of view and construct an anatomical field map through imagination. Summary of the Invention

[0004] The purpose of the present invention is to solve the above problems and provide a solution and device for the direction perception disorder caused by rotating mirror, so as to solve the problem that it is difficult to determine the adjacent tissue structure outside the part after the endoscope is rotated during examination of lesions in the wall of the upper gastrointestinal tract.

[0005] In order to solve the above problems, the present invention provides the following technical solutions:

[0006] On the one hand, a solution to the obstruction of direction perception caused by rotating mirrors includes

[0007] Obtaining the position information of the endoscope in the electromagnetic navigation system at the target position of the lumen and the corresponding intraluminal image as a reference position;

[0008] Obtain the trajectory pose of the endoscope after adjusting the field of view in the electromagnetic navigation system and the corresponding intraluminal image, and determine the Euler angle of each trajectory point based on the trajectory pose;

[0009] According to the angle difference between the reference pose information and the current trajectory pose, the mirror rotation angle is obtained and corresponds to the corresponding intraluminal image;

[0010] According to lumen imaging Figure 3Three-dimensional reconstruction of the lumen and its adjacent tissues, and the rotated lumen and its adjacent tissues are obtained by rotating according to the rotation angle of the rotatable mirror and the corresponding image in the lumen.

[0011] In a preferred embodiment, before determining the reference pose, the electromagnetic navigation device is modified, specifically:

[0012] A new acquisition card is connected to the endoscope and the terminal; the acquisition card acquires the image in the lumen under the endoscope, and the terminal acquires the trajectory pose; the image in the lumen and the corresponding trajectory pose are corresponded.

[0013] In a preferred embodiment, obtaining the trajectory pose of the endoscope in the electromagnetic navigation system and the corresponding image in the lumen, and determining the Euler angle of each trajectory point according to the trajectory pose includes:

[0014] The trajectory point includes a quaternion vector and a displacement vector, and a rotation matrix is obtained according to the two;

[0015] According to the rotation matrix and the set rotation axis order, the rotation angles of the XYZ axes are obtained.

[0016] In a preferred embodiment, obtaining the rotation angle of the rotatable mirror according to the angle difference between the pose information of the reference pose and the current trajectory pose, and corresponding it to the corresponding image in the lumen includes:

[0017] Calculate the angle difference between the reference pose and the current trajectory point pose. If the angle difference is positive, it is clockwise rotation; if the angle difference is negative, it is counterclockwise rotation;

[0018] When it is clockwise, subtract the angle of the current trajectory point pose from the angle of the reference pose to get a difference. If the difference is less than zero, add 360° to get the final rotation degree;

[0019] When it is counterclockwise, subtract the angle of the reference pose from the angle of the current trajectory point pose to get a difference. If the difference is less than zero, also add 360° to the difference to get the final rotation degree.

[0020] In a preferred embodiment, according to the lumen image Figure 3 Three-dimensional reconstruction of the lumen and its adjacent tissues includes:

[0021] The lumen image is input into a preset three-dimensional medical image segmentation model, and the lumen image is spatially reconstructed and integrated into a three-dimensional visualization scene by using a visualization tool to obtain the reconstructed three-dimensional lumen and its adjacent tissues.

[0022] In a preferred embodiment, obtaining the rotated lumen and its adjacent tissues by rotating according to the rotation angle of the rotatable mirror and the corresponding image in the lumen includes:

[0023] Obtain all the intraluminal images during the process of adjusting the visual field from the reference pose, and divide them into multiple groups with the same number. Each group is numbered in sequence; calculate the angular difference between the pose of the first frame image and the pose of the last frame image in each group as the rotation mirror angle, and obtain multiple rotation mirror angles;

[0024] According to multiple rotation mirror angles, sequentially adjust the three-dimensional reconstructed lumen and its adjacent tissues to the intraluminal image when the front face is in the reference pose, and obtain the view of the lumen and its adjacent tissues after adjusting the visual field.

[0025] In a second aspect, an electromagnetic navigation rotation angle calculation device is used to implement a solution method for the direction perception obstacle caused by the rotation mirror; it includes:

[0026] An endoscope for viewing the situation inside the lumen;

[0027] An electromagnetic navigation device, including a sensor and a magnetic field generator. The sensor is fixed at the end of the endoscope, and the magnetic field generator is located beside the patient; it is used to record the position and pose of the endoscope end and the microscopic image information at the corresponding moment;

[0028] An acquisition card for acquiring endoscope images, which is connected to the endoscope and the terminal for controlling the electromagnetic navigation device;

[0029] A three-dimensional medical image segmentation model is used to input the lumen image, and use a visualization tool to spatially reconstruct the lumen image and integrate it into a three-dimensional visualization scene to obtain the reconstructed three-dimensional lumen and its adjacent tissues.

[0030] In a third aspect, an electronic device includes a memory and a processor. When a computer-readable instruction stored in the memory is executed by the processor, the processor executes a solution method for the direction perception obstacle caused by the rotation mirror.

[0031] In a fourth aspect, a computer-readable storage medium stores a computer program. When the computer program runs on a computer, the computer executes a solution method for the direction perception obstacle caused by the rotation mirror.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] (1) When performing digestive endoscopy examination, the present invention can understand the rotation direction and degree of the endoscope without departing from the original examination habits and techniques. After rotating to the best visual field, not only can clearly see the internal situation of the lumen, but also can clearly know the adjacent tissues outside the lumen under this visual field.

[0034] (2) After using the present invention, there is no need for repeated endoscope training, learning, and memory perception of adjacent tissues, getting rid of the need for proficiency in endoscope skills and reducing the operation difficulty.

[0035] (3) During the surgical navigation of the present invention, the information of the rotatable endoscope can be input into the system to guide the three-dimensional model to rotate accordingly, so as to give a direct visual cue of the correct anatomical position corresponding to this field of view.

[0036] (4) After guiding the doctor to perceive the correct tube wall direction in the current field of view, it can assist the doctor in differential diagnosis of, for example, intramural protuberant lesions and extraluminal compression, reduce the diagnostic difficulty and misdiagnosis rate, and avoid unnecessary repeated examinations for patients. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings, where:

[0038] Figure 1 is the acquisition interface after re - programming the software for the modified electromagnetic navigation device;

[0039] Figure 2 is the standard field - of - view diagram with the spine facing down and the trachea facing up and the pose information of the current trajectory point;

[0040] Figure 3 is the three - dimensional reconstructed model rotating with the rotatable endoscope angle I;

[0041] Figure 4 is the three - dimensional reconstructed model rotating with the rotatable endoscope angle II;

[0042] Figure 5 is the working flow chart of this embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0043] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the following will further describe the present invention in detail in conjunction with... Figures 1 to 5 The described embodiments should not be regarded as limitations of the present invention. All other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0044] The objective of this embodiment is to solve the direction perception obstacle caused by the rotation of the endoscope during the doctor's endoscopic diagnosis and treatment, and provide a method that can be used in the navigation of intraluminal surgeries such as digestive endoscopy surgeries, calculate the doctor's rotatable endoscope angle, so as to guide the doctor to perceive the internal situation of the lumen and clearly know the situation of the adjacent tissues outside the lumen in this field of view.

[0045] As Figure 5As shown in the figure, this embodiment proposes a solution to the direction perception disorder caused by the rotary mirror, and its features include the following steps:

[0046] 1) Existing electromagnetic navigation devices can only collect the motion trajectory of an object through sensors and output three-dimensional coordinate information, but cannot obtain the corresponding field of view map under the current trajectory. To solve the rotary mirror problem and assist doctors in perceiving the four walls of the esophageal lumen, we need to record the endoscopic images at the current pose simultaneously. Therefore, we modify the electromagnetic navigation device and write acquisition software to complete the one-to-one correspondence between the trajectory pose and the endoscopic RGB image. The specific operations are as follows:

[0047] ① Add a capture card. One end is connected to the endoscopic host or endoscopic recorder through an HDMI interface to collect the endoscopic field of view image, and the other end is inserted into the computer.

[0048] ② Use the existing serial port programming pyserial library in python to send a PHSR request for the corresponding numbered sensor to the electromagnetic navigation serial port. The PHSR request is the request number provided by the electromagnetic navigation system to obtain the pose. After the electromagnetic navigation system receives the request, it returns the pose of the sensor at the current moment.

[0049] ③ Use the existing image processing opencv library in python to read the endoscopic image at the current moment collected by the capture card. Based on the above principle, write software to collect the trajectory and the corresponding endoscopic field of view image, as Figure 1 shown.

[0050] 2) Fix the sensor in the electromagnetic navigation device at the endoscopic tip, and place the magnetic field generator beside the patient, so as to record the position and pose of the endoscopic tip and the information such as the endoscopic image at the corresponding moment.

[0051] 3) When the endoscopic tip reaches the pharyngeal region, lock the image to obtain a standard endoscopic anatomical field of view map with the spine facing down and the trachea facing up; mark the pose information of the endoscopic tip corresponding to this standard anatomical field of view map, as Figure 2 shown, and use it as a reference.

[0052] 4) Subsequently, crack the trajectory information collected by the electromagnetic navigation device and convert it into Euler angles: The data of each trajectory point of the endoscopic tip obtained contains a quaternion vector and a displacement vector. The quaternion vector represents the rotation information of this point on the XYZ axes, and the displacement vector represents the coordinate values of this point on the XYZ axes. Based on the above information, calculate the rotation degree:

[0053] ① Obtain a 4×4 rotation and translation matrix from the quaternion and translation vector:

[0054] Data given:

[0055] · Quaternion q = (w, x, y, z): Used to describe the rotation on the XYZ axes.

[0056] · Translation vector t = (tx, ty, tz): Used to describe the translation along the XYZ axes.

[0057] ② Conversion from quaternion to rotation matrix:

[0058] The quaternion q = (w, x, y, z) can be converted into a rotation matrix R (3x3), where the calculation formula for the rotation matrix R is:

[0059]

[0060] ③ Extracting XYZ Euler angles from the rotation matrix

[0061] Given the rotation matrix R (a 3×3 matrix obtained from the quaternion), we can extract the rotation angles around the X, Y, and Z axes from the rotation matrix according to the definition of Euler angles. There are many ways to define Euler angles, and common ones include orders such as XYZ, ZYX, etc. We usually use the XYZ order, that is, first rotate around the X axis, then around the Y axis, and finally around the Z axis.

[0062] Extracting Euler angles (XYZ order) from the rotation matrix:

[0063] Given the rotation matrix R:

[0064]

[0065] ④ Calculation process of Euler angles

[0066] Calculating the angle φ around the X axis:

[0067] φ = atan2(R 32 , R 33 )

[0068] This represents the rotation angle around the X axis. atan2 is an arctangent function that returns an angle and can handle situations in different quadrants.

[0069] Calculating the angle θ around the Y axis:

[0070]

[0071] This represents the rotation angle around the Y axis. Since θ may vary between -90° and 90°, the square root is used here to avoid gimbal lock.

[0072] Calculating the angle ψ around the Z axis:

[0073] ψ = atan2(R 21 , R 11 )

[0074] This represents the rotation angle around the Z axis.

[0075] 5) Calculate the degree difference between the current frame and the standard frame: Since each point has been converted into the rotation degree of the current frame relative to the coordinate system, the total rotation degree can be calculated by subtracting the rotation degree of the first point on the z-axis from that of the last point on the z-axis. However, since the rotation degree can only be represented from -180° to 180°, the calculation process of the degree needs to be processed as follows:

[0076] ① First, determine whether it is a clockwise rotation or a counterclockwise rotation (if the rotation degree gradually increases from 0° to 180°, it is judged as a counterclockwise rotation; if it gradually decreases from 180° to 0°, it is judged as a clockwise rotation);

[0077] ② If it is a clockwise rotation, subtract the angle of the current trajectory point pose from the angle of the reference pose to get a difference. If the difference is less than zero, add 360° to get the final rotation degree. If it is a counterclockwise rotation, subtract the angle of the reference pose from the angle of the current trajectory point pose to get a difference. If the difference is less than zero, also add 360° to the difference to get the final rotation degree.

[0078] 6) Input the patient's CT image into the existing totalsegmentator model, use the Reslice function provided by VisualizationToolkit (VTK) to perform spatial reconstruction on the patient's original CT image and integrate it into the 3D visualization scene, and use the polydata mapper to display the.vtp data structure after 3D reconstruction.

[0079] 7) Use the data collected by the improved electromagnetic navigation device to obtain all the intraluminal images during the process from the reference pose to the completion of the field of view adjustment, and divide them into multiple groups with the same number. Each group is numbered in sequence; calculate the angle difference between the pose of the first frame and the pose of the last frame of each group as the scope angle to obtain multiple scope angles; for example, write a loop from number 1 to n through coding, and calculate the difference between the degree of the current frame and the previous frame each time a loop is performed to calculate the scope angle.

[0080] 8) Use the computer mouse to place the reconstructed 3D model according to the standard human body position, aligning the front view of the human eye with the tube wall field of view at the 12 o'clock direction in the standard frame, that is, aligning with the trachea surface. After outputting the degree difference, use the method of rotating around the axis built into the vtk library to rotate the 3D model around the z-axis of the global coordinate system by the difference from the previous frame, so that the current object is rendered onto the page, and the corresponding 3D model will rotate accordingly, so as to obtain the extra-luminal structure corresponding to the tube lumen field of view at the 12 o'clock direction under the endoscope as the rotated 3D model seen by the current human eye, laying a foundation for comprehensive surgical navigation, as Figure 3 and Figure 4 shown.

[0081] An electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor; when the processor executes the computer program, steps of a solution method for direction perception obstacles caused by a rotary mirror are implemented.

[0082] The electronic device can be a desktop computer, a notebook, a palm computer, a cloud server and other electronic devices. The electronic device can include but is not limited to a processor and a memory. Those skilled in the art can understand that the figure is only an example of the electronic device and does not constitute a limitation on the electronic device, and may include more or fewer components than shown, or different components.

[0083] The processor can be a Central Processing Unit (CPU), or other general-purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field-Programmable Gate Arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc.

[0084] The memory can be an internal storage unit of the electronic device, for example, the hard disk or memory of the electronic device. The memory can also be an external storage device of the electronic device, for example, a plug-in hard disk equipped on the electronic device, a SmartMedia Card (SMC), a Secure Digital (SD) card, a Flash Card, etc. The memory can also include both the internal storage unit and the external storage device of the electronic device. The memory is used to store the computer program and other programs and data required by the electronic device.

[0085] In several embodiments provided in the present application, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architectures, functions, and operations of devices, methods, and computer program products according to multiple embodiments of the present invention. In this regard, each block in the flowchart or block diagram may represent a module, a program segment, or a part of code, and the module, program segment, or part of code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than marked in the accompanying drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, and the combination of blocks in the block diagram and / or flowchart, can be implemented by a dedicated hardware-based system for performing the specified functions or actions, or can be implemented by a combination of dedicated hardware and computer instructions.

[0086] In addition, each functional module in various embodiments of the present invention may be integrated together to form an independent part, or each module may exist alone, or two or more modules may be integrated to form an independent part.

[0087] If the above functions are implemented in the form of software function modules and sold or used as an independent product, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. It should be noted that in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including", or any other variation thereof is intended to cover non-exclusive inclusion, so that a process, method, article, or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article, or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, article, or device including the element.

[0088] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention. It should be noted that similar reference numerals and letters indicate similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0089] As mentioned above, the above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or replacements, which should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A solution to the direction perception disorder caused by the rotary mirror, characterized in that obtain the pose information of the endoscope in the electromagnetic navigation system for the target position of the lumen and the corresponding in-lumen image as the reference pose; obtain the trajectory pose of the endoscope after adjusting the field of view in the electromagnetic navigation system and the corresponding in-lumen image, and determine the Euler angle of each trajectory point according to the trajectory pose; obtain the rotary mirror angle according to the angle difference between the pose information of the reference pose and the current trajectory pose, and correspond it to the corresponding in-lumen image; three-dimensionally reconstruct the lumen and its adjacent tissues according to the lumen image, and rotate the lumen and its adjacent tissues after rotation according to the rotary mirror angle and the corresponding in-lumen image.

2. The solution method according to claim 1, wherein, Before determining the reference pose, it also includes modifying the electromagnetic navigation device, specifically: add a capture card to connect the endoscope and the terminal; the capture card captures the in-lumen image under the endoscope, and the terminal captures the trajectory pose; correspond the in-lumen image and the corresponding trajectory pose.

3. The solution method according to claim 1, wherein Obtaining the trajectory pose of the endoscope in the electromagnetic navigation system and the corresponding in-lumen image, and determining the Euler angle of each trajectory point according to the trajectory pose includes: the trajectory point includes a quaternion vector and a displacement vector, and a rotation matrix is obtained according to the two; According to the rotation matrix and the set rotation axis order, obtain the rotation angles of the XYZ axes.

4. The solution method according to claim 1, characterized in that, Obtaining the rotary mirror angle according to the angle difference between the pose information of the reference pose and the current trajectory pose, and corresponding it to the corresponding in-lumen image includes: calculate the angle difference between the reference pose and the current trajectory point pose, if the angle difference is positive, it is clockwise rotation, if the angle difference is negative, it is counterclockwise rotation; when it is clockwise, subtract the angle of the current trajectory point pose from the angle of the reference pose to get a difference. If the difference is less than zero, add 360° as the final rotation degree; when it is counterclockwise, subtract the angle of the reference pose from the angle of the current trajectory point pose to get a difference. If the difference is less than zero, also add 360° to the difference as the final rotation degree.

5. The solution method according to claim 1, characterized in that, Three-dimensionally reconstructing the lumen and its adjacent tissues according to the lumen image includes: input the lumen image into a preset three-dimensional medical image segmentation model, and use a visualization tool to spatially reconstruct the lumen image and integrate it into a three-dimensional visualization scene to obtain the reconstructed three-dimensional lumen and its adjacent tissues.

6. The solution method according to claim 1, wherein, Rotating the lumen and its adjacent tissues after rotation according to the rotary mirror angle and the corresponding in-lumen image includes: obtain all the in-lumen images during the process from the reference pose to the completion of the field of view adjustment, and divide them into multiple groups with the same number. Each group is numbered in order; calculate the angle difference between the pose of the first frame image and the pose of the last frame image in each group as the rotary mirror angle to obtain multiple rotary mirror angles; According to multiple rotary mirror angles, adjust the three-dimensionally reconstructed lumen and its adjacent tissues to the in-lumen image when facing the reference pose directly in sequence to obtain the view of the lumen and its adjacent tissues after adjusting the field of view.

7. An electromagnetic navigation rotation angle calculation device, characterized in that For implementing a solution to the direction perception disorder caused by the rotary mirror according to any one of claims 1-7; It includes: an endoscope for viewing the situation inside the lumen; an electromagnetic navigation device, including a sensor and a magnetic field generator, the sensor is fixed at the end of the endoscope, and the magnetic field generator is located beside the patient; used to record the position and pose of the endoscope end and the in-lumen image information at the corresponding moment; An acquisition card, which is used to acquire endoscopic images and is connected to an endoscope and a terminal for controlling an electromagnetic navigation device; A three-dimensional medical image segmentation model, which is used to input a lumen image, and uses a visualization tool to spatially reconstruct the lumen image and integrate it into a three-dimensional visualization scene to obtain the reconstructed three-dimensional lumen and its adjacent tissues.

8. An electronic device includes a memory and a processor, and computer-readable instructions are stored in the memory. When the computer-readable instructions are executed by the processor, it is characterized in that The processor is caused to execute the solution method for the direction perception obstacle caused by the rotatable endoscope according to any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, A computer program is stored in the readable storage medium, and when the computer program runs on a computer, the computer is caused to execute a solution method for the direction perception obstacle caused by the rotatable endoscope according to any one of claims 1-6.

Images